The goal of immunotherapy for cancer is to increase the strength of a patient's own immune responses against tumors. Immunotherapy can stimulate the activities of specific components of the immune system against cancer cells or can counteract signals produced by the cancer cells that suppress immune responses.
For example, antibodies have been developed as cancer vaccines which bind specifically to tumor-associated antigens (TAAs), e.g., protein antigens and carbohydrate antigens, on the surface of cancer cells, leading to antibody-dependent cellular cytotoxicity, antibody-dependent phagocytosis, and complement-dependent cell lysis, as well as direct cytostatic and/or cytotoxic effects.
Monoclonal antibody-based anti-cancer vaccines against several carbohydrate TAAs, e.g., Globo H, stage-specific embryonic antigen 3, and stage-specific embryonic antigen 4, have been developed. Yet, the need exists for improved monoclonal antibodies as anti-cancer vaccines having higher affinity for the carbohydrate TAA in order to promote more effective killing of cancer cells and to provide long-lasting resistance to cancer relapse.